Calculating the Astronomical Unit (AU), Astronomers observed the Venus transit from various places. Because of the parallax effect, observers like A and B saw Venus's path shifted on the Sun's face. By trigonometry, this shift & the distance between the observers you can determine the distance to Venus. It's about 0.35 AU, so knowing the distance in miles, you can get the length of the AU in miles. Mona Evans, "Transit of Venus - Measuring the Solar System" http://www.bellaonline.com/articles Solar System, Mona Evans, Paths Shift, Astronom Observational, Venus Paths, Secret Boards, Astronom United, Venus Transitional, Sun Faces
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Space Station, Venus, Sun Credit & Copyright: Tomas Maruska (SAAD) - Explanation: On June 8, 2004 - Venus was not the only celestial object to pass in front of the Sun. A few well-situated photographers caught the International Space Station also crossing the Sun simultaneously.
A modern artist’s impression of Captain Cook and astronomer Charles Green observing the 1769 transit of Venus from Tahiti. Although Green is shown looking through the telescope, both Cook and Green observed simultaneously through identical telescopes. The stamp was issued by Tuvalu in 1979 the bicentenary of Cook's death. (photo: Ian Ridpath) Mona Evans, “Transit of Venus – Captain Cook 1769” www.bellaonline.c...